听神经元的频率调谐

频率作为声音的一个重要参数,在听敏感神经元对声音进行分析和编码过程中扮演重要角色。一般用频率调谐曲线来表示听敏感神经元的频率调谐特性,并用Qn(10,30,50)值表达频率调谐曲线的尖锐程度,Qn值越大,频率调谐曲线也越尖锐,神经元的频率调谐能力越好,对频率的分辨能力越高。从听觉外周到中枢,听敏感神经元的频率调谐逐级锐化,而这种锐化主要是由听中枢的多种抑制性神经递质的作用而产生的,其中起主要作用的是GABA能和甘氨酸能神经递质。此外,离皮层调控,双侧下丘间的联合投射以及弱噪声前掩蔽等因素也会影响听敏感神经元的频率调谐特性。

The frequency tuning of auditory neurons

Frequency is an important parameter of sound.It plays a crucial role in the process of sound analysis and encoding by auditory sensitive neurons.Ordinarily,frequency tuning curve was used to express the frequency tuning characteristic of auditory sensitive neurons and Qn（10,30,50） value to express the sharpness of frequency tuning curve.The higher the Qn value,the sharper the frequency tuning curve and the better of the auditory neurons for frequency tuning and frequency analysis are.The sharpness of frequency tuning of auditory sensitive neurons increases from the auditory periphery to central system,this sharpness is mostly due to synaptic inhibition from several inhibition neuro-transmitter in the auditory central system,among which GABAergic and glycinergic play dominate effect.In addition,corticofugal control,commissure projection of the inferior colliculus,weak noise forward masking and other elements can also influence the frequency tuning characteristic of auditory sensitive neurons.